Answer:
x = 14.5945195193
Explanation:
c² = a²+b²
c² = 7²+10² = 49+100
c² =149. ........take both sides by radical
√c²= √149
c= 12.2065556157
c² = a²+b² = x²
x² = 8²+(12.2065556157)²
x² = 64 + 149
x² = 213. .....take both sides by radical
√x² = √213
x = 14.5945195193